redirection usage in bash shell

Question

Belows are the code what I want to understand:

#!/bin/bash
cat > pl.gp <<EOF
...
CONTENTS
...
EOF

The resultant of this shell script gives a pl.gp file which contains every texts before EOF meets. Does anyone help me understand this powerful redirection usage of shell?

Reading [the Bash manual](http://man7.org/linux/man-pages/man1/bash.1.html) might help. — Some programmer dude, Jun 25 '15 at 08:38
You only execute *one* command, `cat`, therefore there is no ordering. — Some programmer dude, Jun 25 '15 at 08:42
It is a "here document". You have figured it out already, but look up "here documents". — rghome, Jun 25 '15 at 08:44

score 1 · Accepted Answer · answered Jun 25 '15 at 08:36

1

This is called a heredoc.

Everything from the <<EOF up to the following EOF token is fed into the cat process on its stdin. cat (by its nature) will then dump it out into the nominated file via stdout redirection (the > operator)

answered Jun 25 '15 at 08:36

Brian Agnew

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redirection usage in bash shell

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